南岭中段一六矿床绿柱石和白云母矿物学特征及其地质意义  

Mineralogical characteristics and geological significance of beryl and muscovite from Yiliu deposit in middle of Nanling metallogenic belt

作　　者：秦锦华 王成辉[1] 陈毓川[2] 赵如意 QIN JinHua;WANG ChengHui;CHEN YuChuan;ZHAO RuYi(MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Naturals Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;Chinese Academy of Geological Sciences,Beijing 100037,China;State Key Laboratory of Nuclear Resources and Evironment,East China University of Technology,Nanchang 330013,Jiangxi,China)

机构地区：[1]自然资源部成矿作用评价重点实验室中国地质科学院矿产资源研究所,北京100037 [2]中国地质科学院,北京100037 [3]东华理工大学核资源与环境国家重点实验室,江西南昌330013

出　　处：《矿床地质》2022年第5期1025-1041,共17页Mineral Deposits

基　　金：国家社会科学基金重大项目“中国战略性三稀矿产资源供给风险治理机制研究”(编号:19ZDA111);中国地质调查局“中国矿产地质志项目”(编号:DD20160346、DD20190379)共同资助。

摘　　要：南岭多金属成矿带中段南部的一六矿床新发现了花岗伟晶型的Be矿化。为进一步查明其矿化特征和成矿机制,文章对一六矿床中的绿柱石及共生的白云母开展了系统的矿物学和矿物化学研究。结果表明,绿柱石富集Li、Rb、Cs等,贫V、Cr、Mg、Mn,属于低碱-无碱绿柱石。云母的类型为白云母-多硅白云母,富集Li、W、Sn、Nb、Ta、Rb、Cs、Ba、Ga、Zn等元素,相对亏损Be、Mg、Cu、Pb等元素。绿柱石类质同象形式为Al^(3+)→Me^(2+),其中Fe^(2+)对Al^(3+)的替换是绿柱石呈淡蓝色-蓝绿色的主要致色机制。白云母中稀有金属元素富集的机制为:(1) Li+Al^(Ⅵ) ■ Fe^(2+)+Mg(Li_(3)Al_(-1)□_(-1)和Si_(2)LiAl_(-3));(2) Rb^(+) ■ K^(+),Na^(+)。绿柱石中高Cs/Na(apfu)比值,低Mg/Fe(apfu)比值,白云母高Nb、Ta、Cs,低K/Rb、K/Cs比值的特征指示一六矿床Be矿化花岗伟晶岩具有较高的分异演化程度。本次发现和研究为区域Be矿化作用研究提供了基础地质资料,也进一步为稀有金属、钨等矿种的找矿预测提供了思路。Granitic pegmatite-type beryllium mineralization,firstly funded in the Yiliu deposit where is situated in southern part of the middle section of the Nanling polymetallic metallogenic belt.For the further investigation of the mineralization characteristics and metallogenic mechanism,this study focuses on the systematic mineralogy and chemistry of the beryl and associated muscovite.The results show that beryl is enriched in Si,Al,Fe,Li,Rb,Cs,Zn,but depleted in V,Cr,Mg,Mn.It belongs to low alkali—alkali-free beryl type.The type of white mica is mainly muscovite-phengite,which is enriched in Li,W,Sn,Nb,Ta,Rb,Cs,V,Ba,Ga,Zn,and relatively depleted in Mg,Cu,Pb.The isomorphic mechanism of beryl is Al^(3+) ■ Me^(2+),in which the substitution of Al^(3+) by Fe^(2+)dominated the formation of light blue-bluish green in colour of beryl.The enrichment mechanism of rare metal elements in muscovite is by (1) Li+Al^(Ⅵ) ■ Fe^(2+)+Mg (Li_(3)Al_(-1)□_(-1 )and Si_(2)LiAl_(-3)) and (2) Rb^(+) ■ K^(+),Na^(+).The characteristics of high Cs/Na ratio and low Mg/Fe ratio in beryl,high contents of Nb,Ta,Cs and low ratios of K/Rb,K/Cs in muscovite in‐dicate that the beryllium mineralized granitic pegmatite in the Yiliu deposit has a high degree of differentiation.This disco-very and study provided basic geological data for the characteristics of regional beryllium mineralization,and also provided a new insight for further prospecting of rare metals,tungsten and other metallic minerals.

关 键 词：地球化学 绿柱石 白云母 花岗伟晶岩型 一六矿床 南岭 

分 类 号：P618.72[天文地球—矿床学] P578.959[天文地球—地质学] P578.969